National Public Radio's chief executive is stepping down, the network's board of directors announced Thursday.

Ken Stern, who spent 10 years with the company as chief operating officer and chief executive officer, is leaving by "mutual agreement," the board said in a statement. Chairman Dennis L. Haarsager will serve as interim CEO while the board searches for a permanent replacement.

"During his tenure, Ken was instrumental in improving NPR's financial health and for initiating important work extending NPR's reach to various new platforms including satellite and digital distribution," he said. "Under his watch, NPR News significantly increased the number of staff, foreign and domestic bureaus and areas of coverage."

Stern said in a statement that he was proud of NPR's journalistic and financial achievements during his tenure.

"I have enormous respect for the management team I assembled and know they will keep NPR on this successful path," he added.

Founded in 1970, NPR is a nonprofit membership organization that distributes news, talk and entertainment programming via some 860 independently operated public radio stations around the country.